The present invention is directed to a nail. More particularly, the present invention pertains to a radially offset, full-round headed nail and a method of making same.
Nails are often used in power driving tools to quickly and efficiently secure objects such as wood. Generally, nails have a head and an elongated shank and are linearly collated in an adhesive strip made of plastic with or without paper backing material with the shanks oriented in a parallel relationship. The nails are ejected sequentially as the driver blade of the power driving tool strikes each of the heads individually. The nails in the strip are, therefore, spaced apart so that the heads do not interfere with each other during discharge. As a result, because of the size and configuration of full-round heads, only a limited number of full-round head nails may be included in a particular strip.
To increase the number of nails apportioned in a strip, manufacturers have developed off-set nails in which the longitudinal axis of the shank is positioned radially off-center of the head. An offset head generally has a toe and a heel. The toe refers to the greater portion of the offset head that is unsupported by the shank, in the direction opposite to the radial displacement of the shank. The heel refers to the portion of the head unsupported by the shank, in the direction of radial displacement of the shank from the center of the head.
Offset nails allow the pitch, i.e., the distance between the shanks, of the offset nails to be closer together, allowing additional offset nails to be included per strip than traditional nails in a comparable strip. The power driving tool, therefore, needs to be reloaded less often, saving time. Often these offset nails are also redesigned with elongated or non-rounded heads because non-round head nails are easier to form than full-round head nails. Offset full-round head nails, however, are readily identified with concentric round head nails where construction codes define nail heads in specific fastening applications. The round head nails have a full 360 degree rim (as opposed to a 180 degree or other shaped configuration of head) giving extra clamping or, “hold down” so to speak, when the nail is driven into a nailing medium.
When the head of a offset full-round head nail is struck, however, it experiences similar deformations as a non-round head nail. Due to the configuration of the nails in the collated strip, the offset nail is struck at a position not supported by the shank, at the toe. The force of the driving blade can bend the toe of the head if the head is not supported properly or if the head is too thin. In addition, the shank may also bend if the load from the force of the driving blade strike is not distributed through the axis of the shank properly. Furthermore, the junction between the head and the shank may not be strongly attached, thus leading to breakage during nailing and causing the power driving tool to jam or fail.
To compensate for these challenges, offset full-round head nails have been manufactured with thickened heads. In addition, these nails have been manufactured such that the shank is slightly off-center to take advantage of the ability to combine more nails in a strip, but are not fully off-center of the head, leaving a small heel, so that less of a toe is present. However, these solutions require additional material to be used to make the head thicker, and the number of nails per strip is not maximized because of the presence of the heel on the head.
Accordingly, there is a need for an offset head with a full-round head that can be collated to maximize the number of nails in a strip. In addition, it would be desirable for such a nail to withstand large forces without bending or yielding without adding material, and more desirably, using less material than currently known with offset full-round head nails.